1EVP_EncryptInit(3) OpenSSL EVP_EncryptInit(3)
2
6 EVP_CIPHER_CTX_init, EVP_EncryptInit_ex, EVP_EncryptUpdate,
7 EVP_EncryptFinal_ex, EVP_DecryptInit_ex, EVP_DecryptUpdate,
8 EVP_DecryptFinal_ex, EVP_CipherInit_ex, EVP_CipherUpdate, EVP_CipherFi‐
9 nal_ex, EVP_CIPHER_CTX_set_key_length, EVP_CIPHER_CTX_ctrl,
10 EVP_CIPHER_CTX_cleanup, EVP_EncryptInit, EVP_EncryptFinal, EVP_Decryp‐
11 tInit, EVP_DecryptFinal, EVP_CipherInit, EVP_CipherFinal,
12 EVP_get_cipherbyname, EVP_get_cipherbynid, EVP_get_cipherbyobj,
13 EVP_CIPHER_nid, EVP_CIPHER_block_size, EVP_CIPHER_key_length,
14 EVP_CIPHER_iv_length, EVP_CIPHER_flags, EVP_CIPHER_mode,
15 EVP_CIPHER_type, EVP_CIPHER_CTX_cipher, EVP_CIPHER_CTX_nid,
16 EVP_CIPHER_CTX_block_size, EVP_CIPHER_CTX_key_length,
17 EVP_CIPHER_CTX_iv_length, EVP_CIPHER_CTX_get_app_data,
18 EVP_CIPHER_CTX_set_app_data, EVP_CIPHER_CTX_type, EVP_CIPHER_CTX_flags,
19 EVP_CIPHER_CTX_mode, EVP_CIPHER_param_to_asn1,
20 EVP_CIPHER_asn1_to_param, EVP_CIPHER_CTX_set_padding - EVP cipher rou‐
21 tines
22
24 #include <openssl/evp.h>
25 void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *a);
27 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
29 ENGINE *impl, unsigned char *key, unsigned char *iv);
30 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
31 int *outl, unsigned char *in, int inl);
32 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out,
33 int *outl);
34 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
36 ENGINE *impl, unsigned char *key, unsigned char *iv);
37 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
38 int *outl, unsigned char *in, int inl);
39 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *outm,
40 int *outl);
41 int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
43 ENGINE *impl, unsigned char *key, unsigned char *iv, int enc);
44 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
45 int *outl, unsigned char *in, int inl);
46 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *outm,
47 int *outl);
48 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
50 unsigned char *key, unsigned char *iv);
51 int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out,
52 int *outl);
53 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
55 unsigned char *key, unsigned char *iv);
56 int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *outm,
57 int *outl);
58 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
60 unsigned char *key, unsigned char *iv, int enc);
61 int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *outm,
62 int *outl);
63 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *x, int padding);
65 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *x, int keylen);
66 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr);
67 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *a);
68 const EVP_CIPHER *EVP_get_cipherbyname(const char *name);
70 #define EVP_get_cipherbynid(a) EVP_get_cipherbyname(OBJ_nid2sn(a))
71 #define EVP_get_cipherbyobj(a) EVP_get_cipherbynid(OBJ_obj2nid(a))
72 #define EVP_CIPHER_nid(e) ((e)->nid)
74 #define EVP_CIPHER_block_size(e) ((e)->block_size)
75 #define EVP_CIPHER_key_length(e) ((e)->key_len)
76 #define EVP_CIPHER_iv_length(e) ((e)->iv_len)
77 #define EVP_CIPHER_flags(e) ((e)->flags)
78 #define EVP_CIPHER_mode(e) ((e)->flags) & EVP_CIPH_MODE)
79 int EVP_CIPHER_type(const EVP_CIPHER *ctx);
80 #define EVP_CIPHER_CTX_cipher(e) ((e)->cipher)
82 #define EVP_CIPHER_CTX_nid(e) ((e)->cipher->nid)
83 #define EVP_CIPHER_CTX_block_size(e) ((e)->cipher->block_size)
84 #define EVP_CIPHER_CTX_key_length(e) ((e)->key_len)
85 #define EVP_CIPHER_CTX_iv_length(e) ((e)->cipher->iv_len)
86 #define EVP_CIPHER_CTX_get_app_data(e) ((e)->app_data)
87 #define EVP_CIPHER_CTX_set_app_data(e,d) ((e)->app_data=(char *)(d))
88 #define EVP_CIPHER_CTX_type(c) EVP_CIPHER_type(EVP_CIPHER_CTX_cipher(c))
89 #define EVP_CIPHER_CTX_flags(e) ((e)->cipher->flags)
90 #define EVP_CIPHER_CTX_mode(e) ((e)->cipher->flags & EVP_CIPH_MODE)
91 int EVP_CIPHER_param_to_asn1(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
93 int EVP_CIPHER_asn1_to_param(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
94
96 The EVP cipher routines are a high level interface to certain symmetric
97 ciphers.
98 EVP_CIPHER_CTX_init() initializes cipher contex ctx.
100 EVP_EncryptInit_ex() sets up cipher context ctx for encryption with
102 cipher type from ENGINE impl. ctx must be initialized before calling
103 this function. type is normally supplied by a function such as
104 EVP_des_cbc(). If impl is NULL then the default implementation is used.
105 key is the symmetric key to use and iv is the IV to use (if necessary),
106 the actual number of bytes used for the key and IV depends on the
107 cipher. It is possible to set all parameters to NULL except type in an
108 initial call and supply the remaining parameters in subsequent calls,
109 all of which have type set to NULL. This is done when the default
110 cipher parameters are not appropriate.
111 EVP_EncryptUpdate() encrypts inl bytes from the buffer in and writes
113 the encrypted version to out. This function can be called multiple
114 times to encrypt successive blocks of data. The amount of data written
115 depends on the block alignment of the encrypted data: as a result the
116 amount of data written may be anything from zero bytes to (inl +
117 cipher_block_size - 1) so outl should contain sufficient room. The
118 actual number of bytes written is placed in outl.
119 If padding is enabled (the default) then EVP_EncryptFinal_ex() encrypts
121 the "final" data, that is any data that remains in a partial block. It
122 uses standard block padding (aka PKCS padding). The encrypted final
123 data is written to out which should have sufficient space for one
124 cipher block. The number of bytes written is placed in outl. After this
125 function is called the encryption operation is finished and no further
126 calls to EVP_EncryptUpdate() should be made.
127 If padding is disabled then EVP_EncryptFinal_ex() will not encrypt any
129 more data and it will return an error if any data remains in a partial
130 block: that is if the total data length is not a multiple of the block
131 size.
132 EVP_DecryptInit_ex(), EVP_DecryptUpdate() and EVP_DecryptFinal_ex() are
134 the corresponding decryption operations. EVP_DecryptFinal() will return
135 an error code if padding is enabled and the final block is not cor‐
136 rectly formatted. The parameters and restrictions are identical to the
137 encryption operations except that if padding is enabled the decrypted
138 data buffer out passed to EVP_DecryptUpdate() should have sufficient
139 room for (inl + cipher_block_size) bytes unless the cipher block size
140 is 1 in which case inl bytes is sufficient.
141 EVP_CipherInit_ex(), EVP_CipherUpdate() and EVP_CipherFinal_ex() are
143 functions that can be used for decryption or encryption. The operation
144 performed depends on the value of the enc parameter. It should be set
145 to 1 for encryption, 0 for decryption and -1 to leave the value
146 unchanged (the actual value of 'enc' being supplied in a previous
147 call).
148 EVP_CIPHER_CTX_cleanup() clears all information from a cipher context
150 and free up any allocated memory associate with it. It should be called
151 after all operations using a cipher are complete so sensitive informa‐
152 tion does not remain in memory.
153 EVP_EncryptInit(), EVP_DecryptInit() and EVP_CipherInit() behave in a
155 similar way to EVP_EncryptInit_ex(), EVP_DecryptInit_ex and
156 EVP_CipherInit_ex() except the ctx paramter does not need to be ini‐
157 tialized and they always use the default cipher implementation.
158 EVP_EncryptFinal(), EVP_DecryptFinal() and EVP_CipherFinal() behave in
160 a similar way to EVP_EncryptFinal_ex(), EVP_DecryptFinal_ex() and
161 EVP_CipherFinal_ex() except ctx is automatically cleaned up after the
162 call.
163 EVP_get_cipherbyname(), EVP_get_cipherbynid() and EVP_get_cipherbyobj()
165 return an EVP_CIPHER structure when passed a cipher name, a NID or an
166 ASN1_OBJECT structure.
167 EVP_CIPHER_nid() and EVP_CIPHER_CTX_nid() return the NID of a cipher
169 when passed an EVP_CIPHER or EVP_CIPHER_CTX structure. The actual NID
170 value is an internal value which may not have a corresponding OBJECT
171 IDENTIFIER.
172 EVP_CIPHER_CTX_set_padding() enables or disables padding. By default
174 encryption operations are padded using standard block padding and the
175 padding is checked and removed when decrypting. If the pad parameter is
176 zero then no padding is performed, the total amount of data encrypted
177 or decrypted must then be a multiple of the block size or an error will
178 occur.
179 EVP_CIPHER_key_length() and EVP_CIPHER_CTX_key_length() return the key
181 length of a cipher when passed an EVP_CIPHER or EVP_CIPHER_CTX struc‐
182 ture. The constant EVP_MAX_KEY_LENGTH is the maximum key length for all
183 ciphers. Note: although EVP_CIPHER_key_length() is fixed for a given
184 cipher, the value of EVP_CIPHER_CTX_key_length() may be different for
185 variable key length ciphers.
186 EVP_CIPHER_CTX_set_key_length() sets the key length of the cipher ctx.
188 If the cipher is a fixed length cipher then attempting to set the key
189 length to any value other than the fixed value is an error.
190 EVP_CIPHER_iv_length() and EVP_CIPHER_CTX_iv_length() return the IV
192 length of a cipher when passed an EVP_CIPHER or EVP_CIPHER_CTX. It
193 will return zero if the cipher does not use an IV. The constant
194 EVP_MAX_IV_LENGTH is the maximum IV length for all ciphers.
195 EVP_CIPHER_block_size() and EVP_CIPHER_CTX_block_size() return the
197 block size of a cipher when passed an EVP_CIPHER or EVP_CIPHER_CTX
198 structure. The constant EVP_MAX_IV_LENGTH is also the maximum block
199 length for all ciphers.
200 EVP_CIPHER_type() and EVP_CIPHER_CTX_type() return the type of the
202 passed cipher or context. This "type" is the actual NID of the cipher
203 OBJECT IDENTIFIER as such it ignores the cipher parameters and 40 bit
204 RC2 and 128 bit RC2 have the same NID. If the cipher does not have an
205 object identifier or does not have ASN1 support this function will
206 return NID_undef.
207 EVP_CIPHER_CTX_cipher() returns the EVP_CIPHER structure when passed an
209 EVP_CIPHER_CTX structure.
210 EVP_CIPHER_mode() and EVP_CIPHER_CTX_mode() return the block cipher
212 mode: EVP_CIPH_ECB_MODE, EVP_CIPH_CBC_MODE, EVP_CIPH_CFB_MODE or
213 EVP_CIPH_OFB_MODE. If the cipher is a stream cipher then
214 EVP_CIPH_STREAM_CIPHER is returned.
215 EVP_CIPHER_param_to_asn1() sets the AlgorithmIdentifier "parameter"
217 based on the passed cipher. This will typically include any parameters
218 and an IV. The cipher IV (if any) must be set when this call is made.
219 This call should be made before the cipher is actually "used" (before
220 any EVP_EncryptUpdate(), EVP_DecryptUpdate() calls for example). This
221 function may fail if the cipher does not have any ASN1 support.
222 EVP_CIPHER_asn1_to_param() sets the cipher parameters based on an ASN1
224 AlgorithmIdentifier "parameter". The precise effect depends on the
225 cipher In the case of RC2, for example, it will set the IV and effec‐
226 tive key length. This function should be called after the base cipher
227 type is set but before the key is set. For example EVP_CipherInit()
228 will be called with the IV and key set to NULL,
229 EVP_CIPHER_asn1_to_param() will be called and finally EVP_CipherInit()
230 again with all parameters except the key set to NULL. It is possible
231 for this function to fail if the cipher does not have any ASN1 support
232 or the parameters cannot be set (for example the RC2 effective key
233 length is not supported.
234 EVP_CIPHER_CTX_ctrl() allows various cipher specific parameters to be
236 determined and set. Currently only the RC2 effective key length and the
237 number of rounds of RC5 can be set.
238
240 EVP_EncryptInit_ex(), EVP_EncryptUpdate() and EVP_EncryptFinal_ex()
241 return 1 for success and 0 for failure.
242 EVP_DecryptInit_ex() and EVP_DecryptUpdate() return 1 for success and 0
244 for failure. EVP_DecryptFinal_ex() returns 0 if the decrypt failed or
245 1 for success.
246 EVP_CipherInit_ex() and EVP_CipherUpdate() return 1 for success and 0
248 for failure. EVP_CipherFinal_ex() returns 0 for a decryption failure
249 or 1 for success.
250 EVP_CIPHER_CTX_cleanup() returns 1 for success and 0 for failure.
252 EVP_get_cipherbyname(), EVP_get_cipherbynid() and EVP_get_cipherbyobj()
254 return an EVP_CIPHER structure or NULL on error.
255 EVP_CIPHER_nid() and EVP_CIPHER_CTX_nid() return a NID.
257 EVP_CIPHER_block_size() and EVP_CIPHER_CTX_block_size() return the
259 block size.
260 EVP_CIPHER_key_length() and EVP_CIPHER_CTX_key_length() return the key
262 length.
263 EVP_CIPHER_CTX_set_padding() always returns 1.
265 EVP_CIPHER_iv_length() and EVP_CIPHER_CTX_iv_length() return the IV
267 length or zero if the cipher does not use an IV.
268 EVP_CIPHER_type() and EVP_CIPHER_CTX_type() return the NID of the
270 cipher's OBJECT IDENTIFIER or NID_undef if it has no defined OBJECT
271 IDENTIFIER.
272 EVP_CIPHER_CTX_cipher() returns an EVP_CIPHER structure.
274 EVP_CIPHER_param_to_asn1() and EVP_CIPHER_asn1_to_param() return 1 for
276 success or zero for failure.
277
279 All algorithms have a fixed key length unless otherwise stated.
280 EVP_enc_null()
282 Null cipher: does nothing.
283 EVP_des_cbc(void), EVP_des_ecb(void), EVP_des_cfb(void),
285 EVP_des_ofb(void)
286 DES in CBC, ECB, CFB and OFB modes respectively.
287 EVP_des_ede_cbc(void), EVP_des_ede(), EVP_des_ede_ofb(void),
289 EVP_des_ede_cfb(void)
290 Two key triple DES in CBC, ECB, CFB and OFB modes respectively.
291 EVP_des_ede3_cbc(void), EVP_des_ede3(), EVP_des_ede3_ofb(void),
293 EVP_des_ede3_cfb(void)
294 Three key triple DES in CBC, ECB, CFB and OFB modes respectively.
295 EVP_desx_cbc(void)
297 DESX algorithm in CBC mode.
298 EVP_rc4(void)
300 RC4 stream cipher. This is a variable key length cipher with
301 default key length 128 bits.
302 EVP_rc4_40(void)
304 RC4 stream cipher with 40 bit key length. This is obsolete and new
305 code should use EVP_rc4() and the EVP_CIPHER_CTX_set_key_length()
306 function.
307 EVP_idea_cbc() EVP_idea_ecb(void), EVP_idea_cfb(void),
309 EVP_idea_ofb(void), EVP_idea_cbc(void)
310 IDEA encryption algorithm in CBC, ECB, CFB and OFB modes respec‐
311 tively.
312 EVP_rc2_cbc(void), EVP_rc2_ecb(void), EVP_rc2_cfb(void),
314 EVP_rc2_ofb(void)
315 RC2 encryption algorithm in CBC, ECB, CFB and OFB modes respec‐
316 tively. This is a variable key length cipher with an additional
317 parameter called "effective key bits" or "effective key length".
318 By default both are set to 128 bits.
319 EVP_rc2_40_cbc(void), EVP_rc2_64_cbc(void)
321 RC2 algorithm in CBC mode with a default key length and effective
322 key length of 40 and 64 bits. These are obsolete and new code
323 should use EVP_rc2_cbc(), EVP_CIPHER_CTX_set_key_length() and
324 EVP_CIPHER_CTX_ctrl() to set the key length and effective key
325 length.
326 EVP_bf_cbc(void), EVP_bf_ecb(void), EVP_bf_cfb(void), EVP_bf_ofb(void);
328 Blowfish encryption algorithm in CBC, ECB, CFB and OFB modes
329 respectively. This is a variable key length cipher.
330 EVP_cast5_cbc(void), EVP_cast5_ecb(void), EVP_cast5_cfb(void),
332 EVP_cast5_ofb(void)
333 CAST encryption algorithm in CBC, ECB, CFB and OFB modes respec‐
334 tively. This is a variable key length cipher.
335 EVP_rc5_32_12_16_cbc(void), EVP_rc5_32_12_16_ecb(void),
337 EVP_rc5_32_12_16_cfb(void), EVP_rc5_32_12_16_ofb(void)
338 RC5 encryption algorithm in CBC, ECB, CFB and OFB modes respec‐
339 tively. This is a variable key length cipher with an additional
340 "number of rounds" parameter. By default the key length is set to
341 128 bits and 12 rounds.
342
344 Where possible the EVP interface to symmetric ciphers should be used in
345 preference to the low level interfaces. This is because the code then
346 becomes transparent to the cipher used and much more flexible.
347 PKCS padding works by adding n padding bytes of value n to make the
349 total length of the encrypted data a multiple of the block size. Pad‐
350 ding is always added so if the data is already a multiple of the block
351 size n will equal the block size. For example if the block size is 8
352 and 11 bytes are to be encrypted then 5 padding bytes of value 5 will
353 be added.
354 When decrypting the final block is checked to see if it has the correct
356 form.
357 Although the decryption operation can produce an error if padding is
359 enabled, it is not a strong test that the input data or key is correct.
360 A random block has better than 1 in 256 chance of being of the correct
361 format and problems with the input data earlier on will not produce a
362 final decrypt error.
363 If padding is disabled then the decryption operation will always suc‐
365 ceed if the total amount of data decrypted is a multiple of the block
366 size.
367 The functions EVP_EncryptInit(), EVP_EncryptFinal(), EVP_DecryptInit(),
369 EVP_CipherInit() and EVP_CipherFinal() are obsolete but are retained
370 for compatibility with existing code. New code should use EVP_Encryp‐
371 tInit_ex(), EVP_EncryptFinal_ex(), EVP_DecryptInit_ex(), EVP_DecryptFi‐
372 nal_ex(), EVP_CipherInit_ex() and EVP_CipherFinal_ex() because they can
373 reuse an existing context without allocating and freeing it up on each
374 call.
375
377 For RC5 the number of rounds can currently only be set to 8, 12 or 16.
378 This is a limitation of the current RC5 code rather than the EVP inter‐
379 face.
380 EVP_MAX_KEY_LENGTH and EVP_MAX_IV_LENGTH only refer to the internal
382 ciphers with default key lengths. If custom ciphers exceed these values
383 the results are unpredictable. This is because it has become standard
384 practice to define a generic key as a fixed unsigned char array con‐
385 taining EVP_MAX_KEY_LENGTH bytes.
386 The ASN1 code is incomplete (and sometimes inaccurate) it has only been
388 tested for certain common S/MIME ciphers (RC2, DES, triple DES) in CBC
389 mode.
390
392 Get the number of rounds used in RC5:
393 int nrounds;
395 EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GET_RC5_ROUNDS, 0, &nrounds);
396 Get the RC2 effective key length:
398 int key_bits;
400 EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GET_RC2_KEY_BITS, 0, &key_bits);
401 Set the number of rounds used in RC5:
403 int nrounds;
405 EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_SET_RC5_ROUNDS, nrounds, NULL);
406 Set the effective key length used in RC2:
408 int key_bits;
410 EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_SET_RC2_KEY_BITS, key_bits, NULL);
411 Encrypt a string using blowfish:
413 int do_crypt(char *outfile)
415 {
416 unsigned char outbuf[1024];
417 int outlen, tmplen;
418 /* Bogus key and IV: we'd normally set these from
419 * another source.
420 */
421 unsigned char key[] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
422 unsigned char iv[] = {1,2,3,4,5,6,7,8};
423 char intext[] = "Some Crypto Text";
424 EVP_CIPHER_CTX ctx;
425 FILE *out;
426 EVP_CIPHER_CTX_init(&ctx);
427 EVP_EncryptInit_ex(&ctx, EVP_bf_cbc(), NULL, key, iv);
428 if(!EVP_EncryptUpdate(&ctx, outbuf, &outlen, intext, strlen(intext)))
430 {
431 /* Error */
432 return 0;
433 }
434 /* Buffer passed to EVP_EncryptFinal() must be after data just
435 * encrypted to avoid overwriting it.
436 */
437 if(!EVP_EncryptFinal_ex(&ctx, outbuf + outlen, &tmplen))
438 {
439 /* Error */
440 return 0;
441 }
442 outlen += tmplen;
443 EVP_CIPHER_CTX_cleanup(&ctx);
444 /* Need binary mode for fopen because encrypted data is
445 * binary data. Also cannot use strlen() on it because
446 * it wont be null terminated and may contain embedded
447 * nulls.
448 */
449 out = fopen(outfile, "wb");
450 fwrite(outbuf, 1, outlen, out);
451 fclose(out);
452 return 1;
453 }
454 The ciphertext from the above example can be decrypted using the
456 openssl utility with the command line:
457 S<openssl bf -in cipher.bin -K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708 -d>
459 General encryption, decryption function example using FILE I/O and RC2
461 with an 80 bit key:
462 int do_crypt(FILE *in, FILE *out, int do_encrypt)
464 {
465 /* Allow enough space in output buffer for additional block */
466 inbuf[1024], outbuf[1024 + EVP_MAX_BLOCK_LENGTH];
467 int inlen, outlen;
468 /* Bogus key and IV: we'd normally set these from
469 * another source.
470 */
471 unsigned char key[] = "0123456789";
472 unsigned char iv[] = "12345678";
473 /* Don't set key or IV because we will modify the parameters */
474 EVP_CIPHER_CTX_init(&ctx);
475 EVP_CipherInit_ex(&ctx, EVP_rc2(), NULL, NULL, NULL, do_encrypt);
476 EVP_CIPHER_CTX_set_key_length(&ctx, 10);
477 /* We finished modifying parameters so now we can set key and IV */
478 EVP_CipherInit_ex(&ctx, NULL, NULL, key, iv, do_encrypt);
479 for(;;)
481 {
482 inlen = fread(inbuf, 1, 1024, in);
483 if(inlen <= 0) break;
484 if(!EVP_CipherUpdate(&ctx, outbuf, &outlen, inbuf, inlen))
485 {
486 /* Error */
487 EVP_CIPHER_CTX_cleanup(&ctx);
488 return 0;
489 }
490 fwrite(outbuf, 1, outlen, out);
491 }
492 if(!EVP_CipherFinal_ex(&ctx, outbuf, &outlen))
493 {
494 /* Error */
495 EVP_CIPHER_CTX_cleanup(&ctx);
496 return 0;
497 }
498 fwrite(outbuf, 1, outlen, out);
499 EVP_CIPHER_CTX_cleanup(&ctx);
501 return 1;
502 }
503
505 evp(3)
506
508 EVP_CIPHER_CTX_init(), EVP_EncryptInit_ex(), EVP_EncryptFinal_ex(),
509 EVP_DecryptInit_ex(), EVP_DecryptFinal_ex(), EVP_CipherInit_ex(),
510 EVP_CipherFinal_ex() and EVP_CIPHER_CTX_set_padding() appeared in
511 OpenSSL 0.9.7.
5120.9.8b 2005-04-15 EVP_EncryptInit(3)